Bitcoin has nothing to do with increase in criminality rate.Criminality was there even before bitcoin was created.It would exist even if bitcoin dies.Criminals would love to use coins like monero ,zcash which are fully anonymous and not bitcoin which is pseudo anonymous.
You are absolutely right there is nothing to do with criminality because this has very long history and its going with many ways just not with Bitcoins criminal are using many ways for many years its just a mind set that criminality is increasing with this they are using many other methods which governments are unable to check
And in the first place, like fiat money, bitcoin was not made for the criminals as their mode of payment transactions. Bitcoin was designed with good intentions for its users and not for criminals. Hence, criminals can either use bitcoin and fiat money that is the fact.